Ramsey Electronics Ramsey 220 MHZ FM RECEIVER KIT Owners Manual

FR-220 • 11 
RAMSEY “Learn-As-You-Build” KIT ASSEMBLY:  
 
We have a twofold strategy for the order of the following kit assembly 
steps. First, we install parts in physical relationship to each other, so 
theres minimal chance of inserting wires into wrong holes. Second, 
whenever possible, we install in an order that fits our Learn-As-You 
Build Kit building philosophy.    
 
FOR EACH PART, OUR WORD INSTALL ALWAYS MEANS THESE 
STEPS:   
1.  Pick the CORRECT part value to start with.    
2.  Insert it...

FR-220 • 12 
 
Also, if you plan to use an enclosure other than the custom Ramsey 
enclosure and knob kit, you may wish to locate the controls differently 
than provided by the PC board. In this case, the control lugs are wired to 
the PC board using your own insulated hookup wire, kept as short as 
possible for neat installation.    
 
FURTHER COMPONENT INSTALLATION   
 
All directions on the PC board (i.e.: right, left, above, below and so 
forth)  assume orientation of your board as shown in the parts...

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❒16. Install R5, 470 ohms [yellow-violet-brown].    
 
2. SA602 OSCILLATOR-MIXER and VARACTOR TUNING
   
 
❒
17. Install R6, 270 ohms [red-violet-brown]. 
❒18. Install C7, a .001 uf bypass capacitor (marked .001 or 102). 
 
In installing the SA602 IC, you may wish to use an 8-pin DIP socket 
rather than soldering the IC directly to the board. Reasons for doing this 
might include the peace of mind of beginners afraid of damaging the IC, 
or experienced builders testing the merits of the...

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❒29. Install varactor diode D1, it has a small black body with white 
and green bands. The white banded end signifies the cathode side. 
It is important that you have correctly identified D1 as type BB405  
and have not confused it with the common signal diode D2. 
❒30. Install R8, 47K ohms [yellow-violet-orange]. 
❒31. Install R9, 270 ohms [red-violet-brown]. 
❒32. Install C13, .01 uf (marked .01 or 103 or 10nf). 
❒33. Installation of C14. This is the first the electrolytic or polarized...

FR-220 • 17 
3. TRANSISTOR COUPLING & AFC CIRCUITS, VOLUME & 
SQUELCH CONTROLS   
❒38. Install Q2, a 2N3904 transistor. Observe correct positioning of 
the flat side. 
❒39. Install R13, 47K ohms (yellow-violet-orange). 
❒40. Install C20, .001 uf (marked .001 or 102). 
❒41. Install R12, 1K ohms (brown-black-red). 
❒42. Install Q3, 2N3904 transistor. 
❒43. Install R10, 1 megohm (brown--black-green). 
❒44. Install R11, 1K ohms (brown-black-red). 
❒45. Install R22, 2 ohms (red-black-gold). 
❒46. Install C29,...

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❒60. Install C25, .001 uf (marked .001 or 102). 
❒61. Install C26, .01 uf (marked .01 or 103 or 10nf). 
❒62. Install L4, the 455 KHz quadrature coil, soldering the two pins 
and the two mounting tabs. 
❒63. Install U2,  MC3359 IC. As in the case of the SA602 IC, you 
could choose to install an 18-pin IC socket rather than soldering the 
IC directly. Re-read the previous discussion of IC sockets offered for 
the installation of U1. Larger ICs such as the MC3359 require 
considerably more care...

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❒76. Install R15, 470K ohms (yellow-violet-yellow).   
 
5. FINAL CONNECTIONS: THE LM386 AUDIO IC STAGE   
 
You now have a working FM receiver ready for adjustment. The output of 
the MC3359 FM IC simply needs to be boosted to listening level. A few 
more connections, and your receiver will be ready for adjustment and 
testing! Now  would be a good time to review some of your previous work 
and also to make sure you have on hand what youll need for testing: 
antenna, fresh battery, earphone...

FR-220 • 20 
TESTING, ALIGNMENT AND ADJUSTMENT   
 
To prepare the FR220 FM VHF Receiver for reliable monitoring 
operation, you will need these basic tools:    
 
❒1. A useful 220 MHz VHF signal source. 
❒2. Hexagonal, non-metallic coil slug alignment tool for L3. 
❒3. Small screwdriver to adjust L4. 
 
1. Signal source:
 This signal can be from your test bench equipment or 
from a live source such as a local repeater. The live signals are best 
for fine-tuning, but they also have that VHF...